/* Qilin - a Java Pointer Analysis Framework
 * Copyright (C) 2021-2030 Qilin developers
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Lesser General Public License as
 * published by the Free Software Foundation, either version 3.0 of the
 * License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Lesser Public License for more details.
 *
 * You should have received a copy of the GNU General Lesser Public
 * License along with this program.  If not, see
 * <https://www.gnu.org/licenses/lgpl-3.0.en.html>.
 */

package qilin.pta.toolkits.turner;

import java.util.Set;
import qilin.core.PTA;
import qilin.core.PointsToAnalysis;
import qilin.core.builder.MethodNodeFactory;
import qilin.core.pag.LocalVarNode;
import qilin.core.pag.MethodPAG;
import qilin.core.pag.Node;
import qilin.util.graph.MergedNode;
import sootup.core.model.SootMethod;
import sootup.core.types.ReferenceType;

public class ModularMVFG extends AbstractMVFG {
  public static AbstractMVFG findOrCreateMethodVFG(
      PTA prePTA, SootMethod method, OCG hg, MergedNode<SootMethod> sccNode) {
    return method2VFG.computeIfAbsent(method, k -> new ModularMVFG(prePTA, method, hg, sccNode));
  }

  private final MergedNode<SootMethod> sccNode;

  public ModularMVFG(PTA prePTA, SootMethod method, OCG hg, MergedNode<SootMethod> sccNode) {
    super(prePTA, hg, method);
    this.sccNode = sccNode;
    buildVFG();
  }

  @Override
  protected boolean statisfyAddingLoadCondition(Set<SootMethod> targets) {
    for (SootMethod tgtmtd : targets) {
      // the target method is in the same scc with current method.
      if (!tgtmtd.isConcrete() || sccNode.getContent().contains(tgtmtd)) {
        return true;
      }
      if (!(tgtmtd.getReturnType() instanceof ReferenceType)) {
        continue;
      }
      MethodPAG tgtmpag = prePTA.getPag().getMethodPAG(tgtmtd);
      AbstractMVFG tgtVfg = method2VFG.get(tgtmtd);
      assert tgtVfg != null;
      MethodNodeFactory tgtnf = tgtmpag.nodeFactory();
      Node ret = tgtnf.caseRet();
      if (tgtVfg.getCSNodes().contains(ret)) {
        return true;
      }
    }
    return false;
  }

  protected boolean satisfyAddingStoreCondition(int paramIndex, Set<SootMethod> targets) {
    for (SootMethod tgtmtd : targets) {
      // the target method is in the same scc with current method.
      if (!tgtmtd.isConcrete() || sccNode.getContent().contains(tgtmtd)) {
        return true;
      }
      MethodPAG tgtmpag = prePTA.getPag().getMethodPAG(tgtmtd);
      AbstractMVFG tgtVfg = method2VFG.get(tgtmtd);
      assert tgtVfg != null;
      MethodNodeFactory tgtnf = tgtmpag.nodeFactory();
      LocalVarNode parm;
      if (paramIndex == PointsToAnalysis.THIS_NODE) {
        parm = (LocalVarNode) tgtnf.caseThis();
      } else {
        if (tgtmtd.getParameterType(paramIndex) instanceof ReferenceType) {
          parm = (LocalVarNode) tgtnf.caseParm(paramIndex);
        } else {
          continue;
        }
      }
      if (tgtVfg.getCSNodes().contains(parm)) {
        return true;
      }
    }
    return false;
  }
}
